Because of the high dielectric permittivity and rather low T g, the polymers modified with NA are attractive as active dielectric materials in actuators, capacitors, and stretchable electronics, whereas the polymer modified with DR1 may be of interest in nonlinear optical devices.I couldn’t help myself, I HAD to read this season’s buzziest book, The Push by Ashley Audrain. Consequently, the permittivity is only 8.8 at RT, but increases to 22 above the melting temperature, where the dipoles are mobile. However, the polar groups of the polymer modified with DR1 are frozen and thus cannot contribute to the permittivity via orientation polarization. The polymers modified with NA groups have a high permittivity (maximum value of 17.3) at RT, suggesting the polar groups to be mobile and orientation polarization to be effective. The transition temperatures have a strong effect on permittivity as indicated by broadband impedance spectroscopy measurements conducted at different temperatures and frequencies. Dynamic scanning calorimetry shows that the polymers that carry NA groups have a glass transition temperature ( T g) well below room temperature (RT), while the one that carries DR1 groups melts at 55 ☌. For the crystalline monomers, the structures were further proven by single crystal X-ray diffraction.
The prepared monomers and polymers were characterized by different spectral methods and gel permeation chromatography. The synthesis of three novel tetracyclosiloxane monomers modified either with a nitroaniline (NA) or with a Disperse Red 1 (DR1) push–pull group and their ring opening polymerization reaction in the presence of tetramethylammonium hydroxide are presented.
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